1. Field of the Invention
This invention relates to a remote control apparatus for control of,detonation of explosives or other remotely located device. In particular, the invention is particularly directed to a portable radio frequency operated apparatus that includes a transmitter and at least one receiver having multi-functional capabilities for extended range, versatility and mission capability.
2. Description of the Prior Art
Remote activation systems with radio frequency (rf) communication links between transmitter and receiver devices have been used widely in the field of military and industrial demolition:applications. In the past, demolition firing devices that generate an electrical impulse detonation signal at their output have been used to detonate explosives or actuate other devices such as smoke generators. For example, the model XM-122 is such a remote control device currently used by the U.S. armed forces, which provides remote activation of demolition charges by sending an rf-signal from a transmitter to a dedicated receiver which in turn activates a blasting cap in response to a properly coded rf-signal. An improved adaptation of the XM-122 is illustrated in U.S. Pat. No. 5,546,862 entitled xe2x80x9cRemote control adaptor for a detonator system.xe2x80x9d Like other devices that are still in use for demolition purposes, the XM-122 is relatively large, fragile, and heavy, with a limited range and operational capability. Also, this remote detonation device has hybrid circuitry and very large high capacity batteries. The XM-122 is undesirable because of its size, power source and range limitations. The XM-122 has a nominal range of 1 km. When used over dry sand, the XM-122 has an estimated range of 3.3 km. Over frozen tundra, the estimated range of the XM-122 is 0.8 km. Additionally, the capability of the XM-122 does not allow for relay capability between multiple units as performed by the instant invention. Another limitation of the XM-122 when compared to each of the three embodiments of the instant invention""s transmitter/receiver devices is that the instant invention has four unique and three common transmission codes. This means that each receiver can be programmed with seven individual codes (whereas each XM-122 receiver has one unique code). In addition, the XM-122 and similar prior art devices use hybrid circuits, which are labor-intensive and expensive to produce.
Most remote actuation apparatus are rf-sensitive at the receiver. To account for spurious rf-signals, a high-powered transmitter is typically required to make it insensitive, which a portable battery operated system cannot do. Inventions that deal with environmentally insensitive explosive detonation devices include U.S. Pat. No. 5,488,908 entitled xe2x80x9cEnvironmentally insensitive electric detonator system and method for demolition and blasting.xe2x80x9d This teaching describes an electrically activated detonator apparatus that includes a relatively insensitive initiating charge in proximity to the main explosive charge; circuitry having input components to receive an input firing pulse; and output components to provide, through arbitrarily long wires, a high voltage that cause ignition of the main explosive charge. Problems with this system include a lack of range, the need for long wires and is lacking in multi-functional capabilities.
The present invention overcomes these problems and provides an effective, safe, and versatile system to remotely control the detonation of demolition charges and remote operation of equipment, such as beacons, laser markers, radios, weapons and other components that are remotely located.
The invention relates to an apparatus comprising transmitter and receiver devices in three embodiments, whose receivers have controlled outputs of either a) electrical excitation, b) control of a mechanical actuator similar to that shown in U.S. Pat. No. 5,546,862, which is hereby incorporated by reference or c) detonation of an explosive. The invention includes circuitry for electrical power conservation wherein each transmitter and receiver is portable and uses batteries, an rf-circuit that reduces rf-susceptibility of spurious environmental signals and increases safety to personnel using the apparatus by enhanced multi-functional encoding capability to actuate the unit. Methods of use include a wide range of military applications, as well as civilian applications such as avalanche control, forestry service, mining operations and structural demolition as well as others. A transmitter and a first embodiment of the receiver can be used in a relay mode for extended operational range where the receiver is coupled to a transmitter in a daisy-chain repeater fashion. A single transmitter can selectively actuate any combination of multiple receivers using a multiple coding schemes (three are common and four are unique receiver programmable).
Accordingly, several advantages of the present invention are:
(a) To provide a detonation/actuator apparatus that includes a microprocessor-based transmitter and receiver units that each include functional capability of a coding scheme for operational flexibility and enhanced safety. Using this feature, each receiver can be programmed by an rf-link to a set of unique codes assigned to each transmitter. The receiver responds to a common coded signal from any one transmitter or responds only to a transmitter-unique coded signal, thus only one receiver can be targeted for actuation by a transmitter in a multi-receiver set-up. Thus, the operator can use combinations of multiple receivers and transmitters or retain single transmitter function for safety: of personnel.
(b) To provide a detonation/actuator apparatus that can be used in harsh environments wherein each receiver includes a crystal filter that provides high out-of-band rejection while tolerating impedance variations due to antenna placement. The filter is combined with a low power FM detector circuit that provides an FSK signal while maintaining high-sensitivity at a low power consumption rate using a commercially available battery power source (for example, a 9-volt battery).
(c) To provide a detonation/actuator apparatus that includes a housing design that affords varied exposure while allowing for multi-functional capabilities in harsh environments such as submergence in saltwater up to depths of 66 feet and use in harsh climatic temperature extremes between xe2x88x9225 and 140 degrees F.
(d) To provide a detonation/actuator apparatus that includes capabilities that allow for a daisy chain relay mode where one receiver is coupled to a transmitter in a repeat fashion to enable many km range relay of a control signal from a master transmitter.
(e) To provide a detonation/actuator apparatus that includes capabilities that allow for a data link test capability between transmitters and unarmed receivers.
(f) To provide a detonation/actuator apparatus that includes capabilities that allow for a LED user feedback of all operations compatible with night vision equipment.
Still further advantages will become in view of the ensuing detailed description. For a better understanding of the present invention, together with other advantages thereof, reference is made to th e following description taken in connection with the accompanying drawings.